Production of fuel gas from carbonaceous solids



May 26, 1953 J. c. KALBACH PRODUCTION oF FUEL GAS FROM cARBoNAcEoUssoLIns Filed Apri; 3o, 1949 Nwl ' INVENTOR. JoH C. /y Ach' B WWYPatented May 26, 1953 PRODUCTION OF FUEL GAS FROM CARBONACEOUS SOLIDSJohn C. Kalbach, New York, N. Y., assgnor to Hydrocarbon Research, Inc.,New York, N. Y., a corporation of New Jersey Application April 30, 1949,Serial No. 90,645

(Cl. liii- 197) 6 Claims.

This invention relates to a process for the generation of gas of highheating value from solid carbonaceous material. cic aspects, it relatesto the hydrogenation of coal in the presence of a hydrocarbon oil whichis vaporized under reaction conditions to orm a fuel gas of high heatingvalue. An important feature of the present invention is the method `ofcharging solid particles as a dispersion into a zone of elevatedpressure.

The process of the present invention is especially useful as applied tothe production of fuel gases from solid carbonaceous minerals. It iscontemplated that the process will nd particular application to thegasification of coal and similar fuels containing volatilizableconstituents. Various grades of coal may be treated includinganthracite, bituminous coals and lignite.

Waste coals, such as slack coal and the like, are suitable for use inthe present process. The process is also applicable to the treatment ofoil shale.

An object of this invention is to provide an improved process for the.production of gas of high heating value from solid carbonaceousmaterial.

Another object of this invention is to provide an improved process forthe hydrogenation of solid carbonaceous material,

A further object is to provide an improved method for feeding solids toa fiuidized hydrogen ation system operating at a high pressure.

Still another object is to provide an improved method for forming adispersion of solid particles in a vapor stream.

A further object of this invention is to provide an improved process forthe treatment of coal and similar carbonaceous materials containingvolatlizable constituents to produce a fuel gas of high heating value.

Other objects and advantages of this invention will be apparent from thefollowing detailed description.

In accordance with this invention, solid carbonaceous material inparticle form is admixed with a hydrocarbon oil to form a slurry. Thisslurry or suspension of coal in oil is pumped into a reaction Zone Whereit is contacted with a hydrogen-rich gas under conditions of elevatedtemperature and pressure suitable for hydrogenr ation. The hydrocarbonliquid used for the preperation of the slurry is preferably derived fromthe solid carbonaceous material. The oil is vaporized and converted tothe extent that a fluidized bedlof substantially dry solids v ismaintained@ In one of its more spe-` in the reaction zone. Vaporizationof oil within the hydrogenation reaction zone is effective as a meansfor controlling the temperature at which the hydrogenation reaction isconducted.

In one embodiment of the invention, the slurry is passed through aheating zone under elevated pressure wherein it is preheated withoutsubstantial vaporization and the resulting preheated slurry injectedinto the hydrogenation Zone. Unvaporized oil passing to the reactionzone is vaporized, aided by the exothermic heat of hydrogenation, and atthe same time some of the oil may undergo destructive hydrogenationwhereby it is converted to hydrocarbons of lower boiling point. Inanother embodiment of the present invention, substantially all of theoil is vaporized, forming a suspension of coal particles in oil vapor. l

The hydrogenation step is carried out under iluid bed reactionconditions, the hydrogen-rich gas and hydrocarbon oil vapors serving asthe fiuidizing medium for the solid particles of carbona-ceous material.Volatile constituents associated with the solid carbonaceous material,as well as the carbonaceous material and oil, are hydrogenated in thehydrogenation reactor. The resulting product comprises a largeproportion of gaseous constituents of high heating value. Normallyliquid products may be recovered from the product Vgas stream and partor all recycled to the process as the oil for preparation of the slurry.A solid residue or char is produced in the hydrogenation reaction whi-chis suitable for use as a fuel, production of briduettes, production of4hydrogen-containing gas, as by reaction with oxygen and steam, etc. Thehydrogen for the hydrogenation reaction may be produced by gasificationof the char with steam or a mixture of oxygen and steam, as is known inthe art. The present process produces fuel gases of high heating value.

About equal parts of oil and carbonaceous solid by weight form a fluidslurry. Larger amounts of oil may be used if desired. The slurry may bereadily pumped with conventional equipment and passed through pipe linesinto the hydrogenation reactor. The slurry may be sprayed into thestream of hydrogen-rich gas entering the reactor.

,The size of the parti-cles used in making up the slurry is subject toconsiderable variation. The particles may range in size, for example,from a powder to particles of 1/4" in average diameter. The smallerparticlesizes are advantageous in that they facilitate handling andincrease the rate of hydrogenation.

The slurry is preferably preheated before introduction into the reactor.This may be effectively accomplished by passing it through a pipe heaterof conventional design. Part or all of the hydrocarbon oil may bevaporized in the heater. The temperature Iat the outlet of the vheatershould generally Abe `approximately` the temperature at which thereaction is carried out. Thus, the temperature may vary from about 550tc about 1000 F. for the hydrogenation of coal. The heater shouldgenerally be opperated at a pressure at least the same as or higher thanthe pressure at which the reaction is carried out. The reaction pressuremay range frein `about. 750

to 1000 pounds per square inch vgauge or' higher.

It is not necessary to use pure hydrogen for the reaction. A mixture ofhydrogenand carbon oxides, such as lmay be readily obtained ,hy thegasification of carbonaceous solids withisteain or a mixture of oxygenand steam is suitable lor they present" process." Preferablyythe*hydregen cntent of the' lhy'drogen-co'I it'ainn'gV gass Ain excessYof G percehtbyvclume.' In m'ost applications of the prcessdisclosedherein-',"it-iscohtempiateii that 'the'char lor residue frqijn thedrogenation reaction will be reacted with -a'mixture of steam and oxygento produce a' hydrogenrich g'as 'which may be` fedf'dirctly`tothehydrogenation Zone;

` Morev or less cracking of the hydrocarbon oil may take" placewithin'the heating zone.' `At thc same time, somel ofl the"yolatilizable constituents oi" the solid'carbonaceous material may be'released. 'The amun't'of cracking :of hydrocarbons anddistillationcf'fthefcoalinay be controlled bl controlling the temperaureand Contact time of the'fslurr'yinthe'heatiig step."

-A hydrogenation catalyst is 'preferably used to accelerate'th'hydicgnation reaction.' Various" imetals and* metal compzuri'dsysuitable as hydrogenation'`vcatalysts;`A as' V,forv example',nickelfhicll sulfide, oxalate iron'sulee; 'ne @aarsspiefeaav their@ teslurry prir to passing the mixture through the preheater. Hyclr'cgerif'l's'" be' added Ato the simplicit aangetaste@ The 4igureisadiagrammatic: elevational View illustrating v'preferred methci f"i?l1,frY ,1g` out tiieprccsfs f'uisiritetitnl' For simiiity in thetil'ed elfptiOn-f a rrie'frredmot 0f operation of tli'eprocess, (tofollbw, caly is' 'used an example of thesolid arbonac'ccus material.

other and efbaaeais'iffa subst- With feiertage t@ the drawing.. @al f.Saibable partitie Size isjharseethr aan .lips l te. a feed besser.flolriiflicli it befed'in 'resuletled mamita-flte eh, va v 3.1.1 te@meer 4- 01` is Sipg'ied igt-he meer' @rves lief A suitable cataly'st',ysuch asniclxel 'sldefmlay be interlaced t0, the mixer ihrqush ,lge @ysuitably, 11i the 'fQr ef e 'Paste'erf Slrfv *with The mixer 4 isprovided with a suitable stirring mechanisn I for the preparation cfas/bstantially uniform slurry of coal particles inthe'il.v The'slurryproducedwin the mixer'lis withdrawn thrughlineftoa pump 9l Where it issubjected'to increased pressureI and discharged thr'ough'line lI'I'to"a'prehea'ter I2 which risv of conventional design with""the slurrypassing through externally heated pipes. Part y'of the slurry may bepassed'through't'lie preheater and part "of 'the slurry passed-throughline` I3,"or all of theslurry may be' passd'throu'gh' either, asdetermined by control valves I4 and I5.

Gen-

erally, it is desirable to pass at least a portion of the slurry throughthe preheater I2. The slurry, under elevated pressure, is admitted tothe hydrogenation reactor I'I through line I 8 into admixture withhydrogen-rich gas supplied to the hydrogenation Azone through line I 9.The heat ,supplied't/o the hydrogenatlon 'reaction l,zone by lines I 8and 'Ilf'togetherwith the 'exothermic fenergy of the hydrogenationreaction, insures substantially complete vaporization of the oil in theslurry. yaporization of the oil may be acwcompli-shed in'the preheaterin which case the hydrogen-,rich gas entering through line I9 needsiippljf'A r1i5'f;"`of the heat requirements. Qn the the slurry may besupplied to lzone with substantially all of the oil in liquid phasewhereupon sufficient heat is required from the hydrogen-rich gas streamsupplemented by the heat of reaction to vaporize the oil in thehydrogenation zone. In this event. tu@ slueifyimayfbe sprsyegfdirlcuyinto the nulazed Ibedfin the 'hydrogenatlcn sone-or int'o thehydrogen-.rich 'gas stream Yflowing'into the fluidized bed.' In anyevent, the hydrogen-'rich gas and vthe resultant foil vapors' v.passupwardly through the "hydrogenation zone vin contact with alilu-idizedbed' cf'f-soli'd carb'onaceous' material, thev vapors and gaspividingtheluidi'zing mediurnfor agitation-oflthe'lbed of particles. Part of theoil may react -With hydrogen yor otherwise be converted 'to 'gaseousproductsduring the process and some' `oil mayprc'ducedas'a result ofhydroger'i'ation'.'` The 'oil 'vapors' are discharged from `thehydrogenation zone with the'product gas through linle2-I. Solid" residueor char re- 'su-lting from 'the hydrogenation is discharged fronithereactor througlline 22 'as controlled by valve 23K. 'This char maycontain 'a considerable quantity of 'carbon' and is 'suitable for use'as fuel or' for thegeneratidn'of'water gas, synthesis gas or the likeby' reaction 'with -oxygen and steam.

The pressure at which the hydrogenation 4zone is operated'is 'co'trolledby4 valve 25. The pressureand temperaturevdthin the reactor aregenerally keptwithin'the range o'f from'about 750 to about 1000 poundsper square inch gauge :and 000 `t`o"900F." The 'oil ls' recovered fromthe product 'gas stream Iby a're'covery unit 26. Product gases aredischargedithrough line 24 as a fuel gas of `high fheating valuewhilethe oil is recycled through line 2'I to a, mixer 4. Excess oil produced'by Vthe' process may be discharged from the'system through line 28. Oilfrom any outsidesource'may"be"supplied to the process through line 29.The amount 'of oil produced or consumed in' the hydrogenation reactor isa function -of the Vtemperature and pressure' at which the "reaction is'carried out. The quantity of liquid'produc'e'd may be"co`ntrolledbycontrolling the pressure and temperature and a balance 'may be'reached whereby there is no net oil production or loss in the processand the process is self-sucient. The quantity of oil recovered from theoperation mayk be increased bydecreasing the operating temperature or byincreasing the operating pressure and may be decreased'by" increasingthe temperature or by decreasing the pressure:

An"especially important application of the process' of this' invention"is the production of fuel gases from solid carbonaceous materials, suchas coal, by'hydrgenation at elevated pressure's where hydrocarbon oilsare 'not readily availableand are not desired as products.` In sucliacase, by'means of the prsent process all of the oils derived from thecoal are converted to gases simultaneously with conversion of the coal.Sufficient oil is recycled within the system to form a slurry of thecoal feed with the quantity of process oil controlled as describedhereinabove.

Obviously many modications and variations of the invention, ashereinabove set forth, may be made without departing from the spirit andscope thereof and, therefore, only such limitations should be imposed asare indicated in the appended claims.

I claim:

1. In a process for the hydrogenation of a solid carbonaceous materialIat an elevated temperature and pressure, the improvement whichcomprises forming a slurry of said solid carbonaceous material inparticle form with a liquid hydrocarbon which is substantiallycompletely vaporizable under reaction conditions, passing said slurryinto admixture with a hydrogen-rich gas in a hydrogenation zone,vaporizing said liquid hydrocarbon within said hydrogenation Zone,maintaining a dense-phase fluidized bed of said carbonaceous material insaid hydrogenation zone, passing said hydrocarbon vapors andhydrogenrich gas upwardly through said bed thereby effectingfluidization and reaction of said carbonaceous material with hydrogen,and recovering from the reaction zone the products of hydrogenation andvaporized liquid hydrocarbon.

2. A process as defined in claim 1 wherein the hydrogenation reaction iscarried out at a pressure within the range of from about 750 to about1,000 pounds per square inch gauge and at a temperature Within the rangeof from about 600 F. to about 900 F.

3. A process as defined in claim 2 wherein said solid carbonaceousmaterial is coal.

4. A process as dened in claim l wherein a hydrogenation catalyst isadmixed with said slurry.

5. In a process for the production of a fuel gas of high heating value,the improvement which comprises admixing coal in particle form with avaporizable liquid hydrocarbon to form a slurry, passing said slurrythrough a heating Zone Wherein a substantial portion of the hydrocarbonis vaporized, passing said coal particles dispersed in hydrocarbonvapors into a reaction zone into admixture with a hydrogen-rich gas at atemperature Within the range or from about 600 F. to about 900 F. and ata pressure within the range of from about r750 to 1,000 pounds persquare inch gauge, maintaining a dense-phase fludized bed of solidparticles from said coal in said reaction zone, passing said hydrocarbonvapors and hydrogen-rich gas upwardly through said bed thereby effectinguidization thereof and reaction of said solid particles with hydrogen,discharging the resulting products of hydrogenation and hydrocarbonvapors from the reaction zone, and separating normally liquidhydrocarbons from normally gaseous hydrocarbons to produce said fuelgas.

6. In a process for the production of a fuel gas of high heating valuefrom a solid carbonaceous material containing volatilizable constituentsby hydrogenation of said solid carbonaceous material at an elevatedtemperature and pressure, the improvement which comprises forming aslurry of said carbonaceous material in particle form with liquidhydrocarbons, passing said slurry into admixture With a hydrogen-richgas in a reaction zone maintained at an elevated temperature andpressure such that said carbonacecus material is hydrogenated,maintaining a dense-phase luidized bed of said carbonaceous materialundergoing reaction Within said reaction Zone, eiecting vaporization ofsaid liquid hydrocarbons within said reaction zone, passing thehydrocarbon vapors and hydrogen-rich gas upwardly through said bed toeiIect uidization thereof and reaction of said carbonaceous ma terialwith hydrogen, discharging from the reaction zone the products ofhydrogenation and vaporization comprising normally gaseous and normallyliquid hydrocarbons, separating normally liquid hydrocarbons from thenormally gaseous hydrocarbons discharged from said reaction Zone toproduce said fuel gas, forming additional slurry of car-bonaceousmaterial with said normally liquid hydrocarbons, and maintaining thepressure and temperature Within said, reaction zone such that thequantity of liquid hydrocarbons recovered therefrom is just suiiicientfor the preparation of slurry feed to said reaction zone.

JOHN C. KALBACH.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 1,342,790 Bergius June 8, 1920 1,996,009 Krauch et al. Mar.26, 1935 2,414,586 Egloi Jan. 21, 1947 2,438,439 Hemminger Mar. 23, 1948FOREIGN PATENTS Number Country Date 503,183 Great Britain Apr. 3, 1939OTHER REFERENCES Meade: Modern Gasworks Practice, 2nd edition, page 384.

1. IN A PROCESS FOR THE HYDROGENATION OF A SOLID CARBONACEOUS MARETIALAT AN ELEVATED TEMPERATURE AND PRESSURE, THE IMPROVEMENT WHUCH COMPRISESFORMING A SLURRY OF SAID SOLID CARBONACEOUS MATERIAL IN PARTICLE FORMWITH A LIQUID HYDROCARBON WHICH IS SUBSTANTIALLY COMPLETELY VAPORIZIABLEUNDER REACTIOON CONDITIONS, PASSING SAID SLURRY INTO ADMIIXTURE WITH AHYDROGEN-RICH GAS IN A HYDROGENATION ZONE, VAPORIZING SAID LIQUIDHYYDROCARBON WITHIN SAID HYDROGENATION ZONE, MAINTAINING A DENSE PHASEFLUIDIZED BED OF SAID CARBONACEOUS MATERIAL IN SAID HYDROGENATION ZONE,PASSING SAID HYDROCARBON VAPORS AND HYDROGENRICH GAS UPWARDLY THROUGHSAID BED THEREBY EFFECTING FLUIDIZAATION AND REACTION OF SAIDCARBONACEOUS MATERIAL WITH HYDROGEN, AND RECOVER ING FROM THE REACTIONZONE THE PRODUCTS OF HYDROGENATION AND VAPORIZED LIQUID HYDROCARBON